Apparatus for shanking drill steels



Jan. 17, 1939. I JI MONZROLL 2,144,193

APPARATUS FOR SHANKING DRILL STEEL'S Filed June 7. 1937 10242.5 4 11 fir '4 //l w A fjglw Inventor I Attorney Z6 I nzmzz Patented Jan. 17, 1939 UNITED STATES PATENT OFFICE APPARATUS FOR SHANKING DRILL STEELS Jeifroy Monzroll, Montreal, Quebec, Canada.

Application June 7, 1937, Serial No. 146,972

2 Claims.

The present invention relates to apparatus for shanking drill steels and particularly hollow steels.

In a widely used system of shanking hollow drill steels, the pressing and hammering action on the steel during formation of the shank tends to contract or deform the end of the bore. To properly correct such deformation and suitably open the bore, it is necessary to subject the shank to a subsequent end forming operation which requires the use of an end forming tool. This end former must be inserted in the plunger sections of the die and, due to the construction of the forging or sharpening machines commonly used in such shanking operation, providing a limited clearance between the main cylinder and the cross head, the task of properly positioning the end former tool is inconvenient and dangerous and involves considerable additional time in the shank forming operation.

An object of the present invention resides in simplifying the operation of forming the shanks on steels and reducing the time required therefor.

Another object of the invention resides in the provision of means whereby the separate end forming step is eliminated.

A further object of the invention resides in performing the end forming operation simultaneously with the upsetting operation.

Still another object of the invention resides in designing the dolly and plunger sections of the shanking machine so that the end of the shank bore is properly formed during the hammering operation.

Other objects and advantages of the invention will become apparent as the description progresses.

In the accompanying drawing forming a part of this specification and in which like reference characters are employed to designate corresponding parts throughout the same:

Figure l is a side elevational View showing a portion of the steel assembled in operative relation with plunger elements and a dolly,

Figure 2 is. a longitudinal sectional view through the same,

Figure 3 is a side elevational view showing the plunger sections in operative assembly, and the apparatus partly in section,

Figure 4 is a transverse section taken on the line 4-4 of Figure 3,

. Figure 5 is a fragmentary top plan view of the finished shank, partly in section to illustrate the formation of the end of the bore, and

Figure 6 is a fragmentary section through one end of the dolly with the forming pin separated therefrom.

Referring to the drawing, wherein for the purpose of illustration is shown a preferred embodiment of the invention, the numerals l0 and I l designate complementary half-sections of what is commonly known as a plunger, the bottom section 10 being adapted for fitting in the die in the main cylinder of a well-known forging or What is commonly called a sharpening ma chine, while the upper section II is fitted in the die secured to the crosshead of the machine. Heretofore, one end of the plunger was formed to provide a closed end wall when the sections were brought together on the machine. In the present case, however, the semi-circular end walls of the plunger sections I0 and H are formed with complementary semi-circular recesses l2, so that when the sections are clamped together the recesses will define a round central aperture of a diameter less than that of the interior shank forming channels of these sections. The passage forming recesses l2 are also preferably formed 7 sections, indicated at Ill.

The dolly employed in the hammering operation to upset the shank, indicated at I4, is generally round in exterior contour, embodying a cylindrical shank l5 and a head portion iii of increased diameter, providing a flat striking face adapted tostrike the closed end of the plunger during the upsetting operation. Prior to my invention, the upsettingdolly I4 was of solid construction. In my improved structure, the dolly l 4 is formed with a central through bore embodying an inner bore section l6 and an outer bore section II of increased diameter, the bore I1 extending from an intermediate point in the dolly to an enlarged bore or counterbore l8 formed in the striker end of the tool.

Firmly fastened in the bore formation of the dolly and mounted to form a projecting portion is a pin, generally indicated at 20, having an inner relatively long cylindrical shank portion 2| and a collar 22 of increased diameter. Atv the outer portion, the pin 20 embodies a comparatively short shank 23 having a slight taper, corresponding to the taper of the passage forming apertures H. in the plunger, while the outer extremity of this shank is formed with an abruptly tapered point 24. This pin 20 is mounted so that the shank 2| is tightly fitted in thebore l7, while the collar 22 is fitted in the counterbore [8 with the outer face of the collar approximately flush with the striking face of the dolly. The shank portion 23 projects outwardly of the dolly and is shaped to extend through the aperture in the striking end of the plunger, that is, the tapered aperture formed by the complementary semi-circular recesses 12 in the striking end wall of the plunger or upsetter sections. When the dolly is in fully advanced striking position, the tapered or conical point 24 of the dolly pin is adapted to project into the end of the steel, in axial alignment with the bore in the steel, as shown to advantage at Figures 2 and 3.

Thus, during the shanking operation, while the steel, indicated at 26, is in shanking position, that is, gripped in the plunger sections or upsetters l0 and II, and clamped in the dies of the forging machine and being operated upon by the upsetting dolly Hi, the projecting portion of the dolly pin penetrates through the aperture in the walled end of the plunger and the point is driven into the hollow end portion of the steel. Therefore, simultaneously with the shank forming and upsetting operation, the pin 20 functions to prevent contraction or deformation of the end of the bore and forms atapered end portion or countersink, indicated at 21 at Figure 5.

This simultaneous end forming of the bore of the steel not only eliminates the separate end forming step and the necessity of inserting the end former tool in the hot dies, but assures the formation of an accurately centered and tapered end bore opening which will obviate the danger of damaging the water feed tube in drilling machines and also form an effective guide for any subsequent punching operation which may be required to clear the bore at the lug or collar forming section of the steel. It will also eliminate the necessity of re-shaping the shank, which was usually necessary in the former method of operation after the end forming step.

It is to be understood that the form of my invention herein shown and described is to be taken as a preferred example of the same, and that various changes as to the shape, size and arrangement of parts may be resorted to without departing'from the spirit of the invention or the scope of the subjoined claims.

Having thus described my invention, I c1aim:-

1. In apparatus for shanking axially bored steel, a pair of complementary plunger forming sections, each of the said sections being provided at the end wall with recesses adapted to form a round aperture in said end Wall when the sections are in clamping assembly, an upsetting dolly having a striking face adapted to strike against the end walls of the plunger sections, the said dolly being formed with an axial bore, a pin having a fastening shank fitted in the bore in the dolly, a tapered shank on the said pin adapted to project axially from the striking face of the dolly and to extend through the aperture in the plunger sections, and an abruptly tapered point in the outer end of the pin adapted to enter the end of the bore of the steel at each impact stroke of the dolly to prevent deformation of the end of the bore and to form a countersink thereat.

2. In apparatus for shanking axially bored drill steel, a pair of complementary plunger forming sections, each of the said sections being formed to provide an aperture in the end wall when the sections are assembled, a dolly having an end striking face adapted to strike against the end walls of the said sections, the said dolly having an axial bore therein, a pin having a fastening shank adapted to be fitted in the bore of the dolly, a collar formed on the said fastening shank adapted to fit in a counterbore in the dolly, and a shank projecting outwardly of the dolly adapted to extend through the aperture in the plunger sections and into the end of the bore of the steel.

JEFFROY MONZROLL. 

